The impact of glucose-6-phosphate dehydrogenase deficiency(G-6-PD) on the clinical course of sickle cell disease(SCD) is still controversial. The objectives of this study were to determine the ...prevalence of G-6-PD deficiency in patients with SCD and its effect on their clinical course.
A cross-sectional study of 122 SCD patients and 211 healthy blood donors was conducted in Kisangani city. Data were collected through clinical examination supplemented by patient medical records, and laboratory tests based on a survey form. G-6-PD activity was measured by spectrophotometry and the screening for SCD by the HemoTypeSC
®
rapid test. Statistical analysis was done using SPSS ver. 20.0.
The prevalence of G-6-PD deficiency did not differ between SCD and non-SCD subjects, 35.2% vs. 33.6% respectively(p = .767). When comparing the hemoglobin level between SCD patients with and without G-6-PD deficiency, no significant difference was observed. However, in the 6 months prior to the study, SCD patients with G-6-PD deficiency had on average more transfusions than non-deficient SCD patients, 0.64 ± 0.897 vs. 0.24 ± 0.486(p = .004). Similarly, considering the clinical events of the last 12 months prior to the study, there were more hospitalizations, major vaso-occlusive crises and anemia requiring blood transfusion among G-6-PD deficient SCD patients compared to no-deficient, respectively 1.42 ± 1.451vs. 0.76 ± 1.112(p = .007); 1.37 ± 1.092 vs. 0.85 ± 1.014(p = .005); 0.74 ± 0.902 vs. 0.38 ± 0.739 (p = .007).
The prevalence of G-6-PD deficiency in SCD patients was high but did not differ from that observed in controls. In addition, G-6-PD deficiency appeared to worsen the clinical features of SCD. Nevertheless, prospective studies further clarifying this observation are needed.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Leukodystrophies are a heterogeneous group of severe genetic neurodegenerative disorders. A multiple mitochondrial dysfunctions syndrome was found in an infant presenting with a progressive ...leukoencephalopathy. Homozygosity mapping, whole exome sequencing, and functional studies were used to define the underlying molecular defect. Respiratory chain studies in skeletal muscle isolated from the proband revealed a combined deficiency of complexes I and II. In addition, western blotting indicated lack of protein lipoylation. The combination of these findings was suggestive for a defect in the iron-sulfur (Fe/S) protein assembly pathway. SNP array identified loss of heterozygosity in large chromosomal regions, covering the
NFU1
and
BOLA3
, and the
IBA57
and
ABCB10
candidate genes, in 2p15-p11.2 and 1q31.1-q42.13, respectively. A homozygous c.436C > T (p.Arg146Trp) variant was detected in
IBA57
using whole exome sequencing. Complementation studies in a HeLa cell line depleted for
IBA57
showed that the mutant protein with the semi-conservative amino acid exchange was unable to restore the biochemical phenotype indicating a loss-of-function mutation of IBA57. In conclusion, defects in the Fe/S protein assembly gene
IBA57
can cause autosomal recessive neurodegeneration associated with progressive leukodystrophy and fatal outcome at young age. In the affected patient, the biochemical phenotype was characterized by a defect in the respiratory chain complexes I and II and a decrease in mitochondrial protein lipoylation, both resulting from impaired assembly of Fe/S clusters.
Background/Objectives: BRCA1, BRCA2, ATM, and CHEK2 are known cancer predisposition genes (CPGs), but tumor risk in patients with simultaneous pathogenic variants (PVs) in CPGs remains largely ...unknown. In this study, we describe six patients from five families with multiple cancers who coinherited a combination of PVs in these genes. Methods: PVs were identified using NGS DNA sequencing and were confirmed by Sanger. Results: Families 1, 2, and 3 presented PVs in BRCA2 and ATM, family 4 in BRCA2 and BRCA1, and family 5 in BRCA2 and CHEK2. PVs were identified using NGS DNA sequencing and were confirmed by Sanger. The first family included patients with kidney, prostate, and breast cancer, in addition to pancreatic adenocarcinomas. In the second family, a female had breast cancer, while a male from the third family had prostate, gastric, and pancreatic cancer. The fourth family included a male with pancreatic cancer, and the fifth family a female with breast cancer. Conclusions: The early age of diagnosis and the development of multiple cancers in the reported patients indicate a very high risk of cancer in double-heterozygous patients associated with PVs in HR-related CPGs. Therefore, in families with patients who differ from other family members in terms of phenotype, age of diagnosis, or type of cancer, the cascade testing needs to include the study of other CPGs.
Lynch syndrome (LS) and constitutional mismatch repair deficiency (CMMRD) are distinct cancer syndromes caused, respectively, by mono- and bi-allelic germline mismatch repair (MMR) variants. LS ...predisposes to mainly gastrointestinal and genitourinary cancers in adulthood. CMMRD predisposes to brain, haematological, and LS-spectrum cancers from childhood. Two suspected LS patients with first cancer diagnosis aged 27 or 38 years were found to be homozygous for an MMR (likely) pathogenic variant, MSH6 c.3226C>T (p.(Arg1076Cys)), or variant of uncertain significance (VUS), MLH1 c.306G>A (p.(Glu102=)). MLH1 c.306G>A was shown to cause leaky exon 3 skipping. The apparent genotype-phenotype conflict was resolved by detection of constitutional microsatellite instability in both patients, a hallmark feature of CMMRD. A hypomorphic effect of these and other variants found in additional late onset CMMRD cases, identified by literature review, likely explains a LS-like phenotype. CMMRD testing in carriers of compound heterozygous or homozygous MMR VUS may find similar cases and novel hypomorphic variants. Individualised management of mono- and bi-allelic carriers of hypomorphic MMR variants is needed until we better characterise the associated phenotypes.
Neonatal screening programs for sickle cell disease are now widespread in North American and European countries. Most programs apply isoelectric focusing or HPLC to detect hemoglobin variants. ...Because tandem mass spectrometry (MS/MS) is being used for screening of inherited metabolic disorders and allows protein identification, it was worth testing for hemoglobinopathy screening.
We minimized sample preparation and analysis times by avoiding prior purification, derivatization, or separation. We developed a tryptic digestion methodology to screen for the main clinically important variants (Hb S, Hb C, and Hb E) and beta-thalassemia. To ensure proper discrimination between homozygote and heterozygote variants, we selected 4 transitions with good signal intensities for each specific peptide and calculated variant/Hb A ratios for each. Method validation included intra- and interseries variability, carryover, and limit of detection. We also performed a comparative study with isoelectric focusing results on 2082 specimens.
Intraassay imprecision values (CVs) varied between 2.5% and 30.7%. Interassay CVs were between 6.3% and 23.6%. Carryover was <0.03%, and the limit of detection was fixed at 1% of Hb S. According to the MS/MS settings (detection of Hb S, Hb C, Hb E, and beta-globin production defects), the comparative study did not yield any discrepant results between the 2 techniques.
MS/MS is a reliable method for hemoglobinopathy neonatal screening.
Genetic variability related to the catechol-O-methyltransferase (COMT) gene (Val158Met polymorphism) has received increasing attention as a possible modulator of cognitive control functions.
In an ...event-related functional magnetic resonance imaging (fMRI) study, a modified version of the Stroop task was administered to three groups of 15 young adults according to their COMT Val158Met genotype Val/Val (VV), Val/Met (VM) and Met/Met (MM). Based on the theory of dual mechanisms of control (Braver et al., 2007), the Stroop task has been built to induce proactive or reactive control processes according to the task context.
Behavioral results did not show any significant group differences for reaction times but Val allele carriers individuals are less accurate in the processing of incongruent items. fMRI results revealed that proactive control is specifically associated with increased activity in the anterior cingulate cortex (ACC) in carriers of the Met allele, while increased activity is observed in the middle frontal gyrus (MFG) in carriers of the Val allele.
These observations, in keeping with a higher cortical dopamine level in MM individuals, support the hypothesis of a COMT Val158Met genotype modulation of the brain regions underlying proactive control, especially in frontal areas as suggested by Braver et al.
ATP, released at the leading edge of migrating neutrophils, amplifies chemotactic signals. The aim of our study was to investigate whether neutrophils express ATP-gated P2X(1) ion channels and ...whether these channels could play a role in chemotaxis. Whole-cell patch clamp experiments showed rapidly desensitizing currents in both human and mouse neutrophils stimulated with P2X(1) agonists, alphabeta-methylene ATP (alphabetaMeATP) and betagammaMeATP. These currents were strongly impaired or absent in neutrophils from P2X(1)(-/-) mice. In Boyden chamber assays, alphabetaMeATP provoked chemokinesis and enhanced formylated peptide- and IL-8-induced chemotaxis of human neutrophils. This agonist similarly increased W-peptide-induced chemotaxis of wild-type mouse neutrophils, whereas it had no effect on P2X(1)(-/-) neutrophils. In human as in mouse neutrophils, alphabetaMeATP selectively activated the small RhoGTPase RhoA that caused reversible myosin L chain phosphorylation. Moreover, the alphabetaMeATP-elicited neutrophil movements were prevented by the two Rho kinase inhibitors, Y27632 and H1152. In a gradient of W-peptide, P2X(1)(-/-) neutrophils migrated with reduced speed and displayed impaired trailing edge retraction. Finally, neutrophil recruitment in mouse peritoneum upon Escherichia coli injection was enhanced in wild-type mice treated with alphabetaMeATP, whereas it was significantly impaired in the P2X(1)(-/-) mice. Thus, activation of P2X(1) ion channels by ATP promotes neutrophil chemotaxis, a process involving Rho kinase-dependent actomyosin-mediated contraction at the cell rear. These ion channels may therefore play a significant role in host defense and inflammation.
Infertility in couples is a common problem, with both female and male factors contributing to similar extents. Severe, congenital disorders affecting fertility are, however, rare. While ...folliculogenesis and spermatogenesis are generally orchestrated via different mechanisms, some genetic anomalies can impair both female and male gametogenesis. Minichromosome maintenance complex component 9 (MCM9) is involved in DNA repair and mutations of the
gene have been previously reported in females with premature ovarian insufficiency (POI).
is also an emerging cancer risk gene. We performed next-generation and Sanger sequencing of fertility and related genes and hormonal and imaging studies in a kindred whose members had POI and disordered spermatogenesis. We identified a homozygous pathogenic
variant, c.394C>T (p.Arg132*) in three sisters affected by POI due to ovarian dysgenesis and their brother who had normal pubertal development but suffered from non-obstructive azoospermia. Testicular biopsy revealed Sertoli cell-only testicular histopathology. No evidence of early onset cancer was found in the homozygotic family members, but they were all young (<30 years) at the time of the study. In the male patient the homozygous
variant led to normal pubertal development and hormonal levels but caused a Sertoli-cell-only syndrome with non-obstructive azoospermia. In the homozygous females studied, the clinical, hormonal, and gonadal phenotypes revealed ovarian dysgenesis consistent with previous reports. Active screening for potential colorectal and other cancer risks in the homozygotic
subjects has been instigated.
Crohn's disease and ulcerative colitis known as inflammatory bowel diseases (IBD) are chronic immuno-inflammatory pathologies of the gastrointestinal tract. These diseases are multifactorial, ...polygenic and of unknown etiology. Clinical presentation is non-specific and diagnosis is based on clinical, endoscopic, radiological and histological criteria. Novel markers are needed to improve early diagnosis and classification of these pathologies. We performed a study with 120 serum samples collected from patients classified in 4 groups (30 Crohn, 30 ulcerative colitis, 30 inflammatory controls and 30 healthy controls) according to accredited criteria. We compared protein sera profiles obtained with a Surface Enhanced Laser Desorption Ionization-Time of Flight-Mass Spectrometer (SELDI-TOF-MS). Data analysis with univariate process and a multivariate statistical method based on multiple decision trees algorithms allowed us to select some potential biomarkers. Four of them were identified by mass spectrometry and antibody based methods. Multivariate analysis generated models that could classify samples with good sensitivity and specificity (minimum 80%) discriminating groups of patients. This analysis was used as a tool to classify peaks according to differences in level on spectra through the four categories of patients. Four biomarkers showing important diagnostic value were purified, identified (PF4, MRP8, FIBA and Hpα2) and two of these: PF4 and Hpα2 were detected in sera by classical methods. SELDI-TOF-MS technology and use of the multiple decision trees method led to protein biomarker patterns analysis and allowed the selection of potential individual biomarkers. Their downstream identification may reveal to be helpful for IBD classification and etiology understanding.
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